KANO —
The Emir of Kano, Nigeria's second-highest Islamic authority and a revered figure in the largely Muslim north, died on Friday.

Ado Abdullahi Bayero, who was on the throne for half a century, died peacefully in his palace at the age of 83, two palace sources told Reuters.

Though he rarely spoke publicly, he was seen as a critic of Islamist insurgent group Boko Haram, who were suspected to be behind an attack on his convoy in January last year that killed four of his body guards.

The palace at the time said he had escaped unhurt, although he was flown to London for treatment shortly afterwards.

Practicing a Wahabist brand of Islam modeled on the Afghan Taliban, Boko Haram are anti-establishment and often attack Islamic clerics, many of whom they regard as corrupt, self serving and insufficiently strict in their interpretation of the Koran. They killed the Emir of Gwoza Alhaji Idrissa Timta in an attack on his convoy last Friday.

The Emirate of Kano was one of the great Islamic empires that dotted the Sahara from medieval times, profiting from caravan routes connecting Africa's interior with its Mediterranean coast.